Hi kyusanglee,
Thank you for writing with your question. Also, your clever method of asking it.
The problem is that we are not finished exposing the part of the API that you need. Specifically, setInPoint and setOutPoint are not yet available.
We know that this is a very important call for developers, and it will be ready soon. (weeks, not months)
Below is a link to another message with a similar request, and a workaround.
Thank you for developing for Premiere Pro.
-Dan